The present invention relates in general to a method for transmitting a radio resource control (RRC) message in an asynchronous mobile communication system; and, more particularly to a method for transmitting a radio resource control (RRC) message between an asynchronous mobile station and an asynchronous mobile network regardless of an operating type of a core network.
In a conventional synchronous mobile telecommunications system, a synchronous mobile station is connected to a synchronous radio network (for example, a CDMA-2000 radio network), and a synchronous radio network is connected to an ANSI-41 core network.
In a conventional asynchronous mobile telecommunications system, an asynchronous mobile station is connected to an asynchronous radio network (for example, a universal mobile telecommunication system (UMTS) terrestrial radio access network (UTRAN)), and an asynchronous radio network is connected to a global system for mobile communication-mobile application part (GSM-MAP) core network.
FIG. 1A is a view showing the core network interface architecture of the conventional synchronous mobile telecommunications system. In this drawing, the reference numeral 11 denotes a synchronous mobile station, 12 denotes a synchronous radio network (i.e., a code division multiple access-2000 (CDMA-2000) radio network) which performs a data interfacing operation with the synchronous mobile station 11 and includes a synchronous base transceiver station/base station controller (BTS/BSC), and 13 denotes a synchronous core network (i.e., an ANSI-41 core network) which is connected to the synchronous radio network 12 and includes a synchronous mobile services switching center (MSC) 14.
In the above core network interface architecture of the conventional synchronous mobile telecommunications system, the synchronous mobile station 11 can be connected to only the synchronous radio network 12 as well known to one skilled in the art, which is in turn connected to the synchronous core network 13, thereby allowing the synchronous mobile station 11 to be interfaced with only the synchronous core network 13.
FIG. 1B is a view showing the core network interface architecture of the conventional asynchronous mobile telecommunications system. In this drawing, the reference numeral 21 denotes an asynchronous mobile station, 22 denotes an asynchronous radio network (i.e., a UTRAN) which includes a Node B which is similar to base transceiver station (BTS) and a radio network controller (RNC), and 23 denotes an asynchronous core network which includes an asynchronous mobile services switching center (MSC) 24 connected to the UTRAN 22.
In the above core network interface architecture of the conventional asynchronous mobile telecommunications system, the asynchronous mobile station 21 is connected to the asynchronous radio network 22 (i.e., UTRAN) which is in turn connected to the asynchronous core network 23, thereby allowing the asynchronous mobile station 21 to perform a data interfacing operation with the asynchronous core network 23.
FIG. 2A is a view showing the layered protocol structure of the conventional synchronous mobile telecommunications system. In this drawing, the reference numeral 30 denotes a synchronous mobile station, 40 a synchronous radio network and 50 a synchronous core network connected to the synchronous radio network 40.
The synchronous mobile station 30 comprises a layer331, a layer235 and a layer136. The layer331 includes a synchronous call control (CC) entity 32 for management of a call and a synchronous mobility management (MM) entity 33 for management of a mobility.
The layer136 is a physical layer which offers data transport services to higher layers and transfers transport blocks over a radio interface.
The layer235 is a data link layer which includes following sub layers, a medium access control (MAC) sub layer and a radio link control (RLC) sub layer. However, the sub layers are not shown in this drawing.
The MAC sub layer offers data transfer services on logical channels to a higher layer (RLC sub layer) and on transport channels to a lower layer (the physical layer 36). The MAC sub layer is responsible for mapping of the logical channel onto the appropriate transports channel.
The RLC sub layer offers data transfer services on primitive to a higher layer and on logical channels to a lower layer (MAC sub layer). Also, the RLC sub layer performs error correction, duplicate detection, ciphering and flow control of the data.
The layer331 is a network layer which includes following sub layers, a synchronous radio resource (RR) sub layer, a synchronous call control (CC) entity 32 and a mobility management (MM) entity 33. In synchronous system, the synchronous RR sub layer is not apparently separated from the others in the layer331.
The RR sub layer offers data transfer services on primitive to a lower layer (RLC sub layer) and handles a radio resource control signaling of the layer331 between a user equipment (UE) and a synchronous radio network. The RR sub layer manages a radio resource. Also, the RR sub layer assigns/re-configures/releases the radio resource to UE/UTRAN.
The CC entity handles a call control signaling of layer3 between the UEs and the synchronous radio network.
The MM entity handles a mobility management signaling of layer3 between the user equipments (UEs) and the synchronous radio network.
The layers 3 to 131, 35 and 36 in the synchronous mobile station 30 communicate with corresponding layers 41, 45 and 46 in the synchronous radio network 40.
The synchronous radio network 40 comprises a layer341, a layer245 and a layer146. The layers 3 to 1 in the synchronous radio network 40 correspond respectively to those in the synchronous mobile station 30.
The layers 3 to 141, 45 and 46 in the synchronous radio network 40 communicate with corresponding layers 31, 35, 36, 51, 55 and 56 in the synchronous mobile station and the synchronous core network 50.
The synchronous core network 50 comprises a layer351, a layer255 and a layer156. The layers 3 to 1 in the synchronous radio network 50 correspond respectively to those in the synchronous mobile station 30.
The layers 3 to 151, 55 and 56 in the synchronous core network 50 communicate with corresponding layers 41, 45 and 46 in the synchronous radio network 40.
In the conventional synchronous mobile station and radio network as the layered protocol structure, the synchronous mobile station 30 receives a Sync channel message from the synchronous radio network 40 over a Sync channel and acquires information necessary to its connection to the synchronous core network 50, including information related to the synchronous core network 50 and information about the synchronous radio network 40, from the received Sync channel message.
In other words, for interfacing with the synchronous ANSI-41 network via the synchronous radio network, the synchronous mobile station acquires system information (i.e., information related to the radio network and core network) through a system determination sub-state, a pilot channel acquisition sub-state, a Sync channel acquisition sub-state and a timing changing sub-state after it is powered on.
FIG. 2B is a view showing the layered protocol structure of the conventional asynchronous mobile telecommunications system. In this drawing, the reference numeral 60 denotes an asynchronous mobile station, 70 a UTRAN and 80 an asynchronous core network.
The asynchronous mobile station 60 comprises a layer361, a layer265 and a layer166. In particular, the layer361 includes a non-access stratum (NAS) part and an access stratum (AS) part. The NAS part includes an asynchronous call control (CC) part 62 for management of a call and an asynchronous mobility management (MM) part 63 for management of a mobility. The AS part includes an asynchronous radio resource control (RRC) part. In the asynchronous system, the asynchronous RRC sub layer is apparently separated from the NAS part. Functions of the asynchronous RRC sub layer are similar with those of the synchronous RR sub layer.
The UTRAN 70 comprises a layer371, a layer273 and a layer174. The layer371 of the UTRAN 70 has no NAS part having asynchronous CC part and asynchronous MM part. The layers 3 to 1 of the UTRAN 70 are connected and correspond respectively to those in the asynchronous mobile station 60 and those in the asynchronous core network 80. However, since the UTRAN 70 does not have the NAS part, i.e., the asynchronous CC part and the asynchronous MM part, the NAS parts of the asynchronous mobile station 60 and the asynchronous core network 80 are coupled to each other not through the UTRAN 70.
The asynchronous core network 80 comprises a layer3 having a NAS part 81 connected to that of the asynchronous mobile station 60 and a AS part, a layer285 and a layer186 connected respectively to those in the UTRAN 70. The NAS part comprises an asynchronous CC part 82 for management of a call and an asynchronous MM part 83 for management of a mobility.
Functions of the layer 3 to 1 of the asynchronous system are similar with those of the synchronous system except for an operating type. Therefore, detailed description of the layer 3 to 1 will be skipped.
The more detailed descriptions about layered protocol structures are well taught in 3rd Generation Partnership Project (3GPP), Technical Specification Group (TSG)xe2x80x94Radio Access Network (RAN): 3G TS25.301 (Radio Interface Protocol Architecture), 3G TS25.302 (Services provided by the physical layer), 3G TS25.321 (MAC Protocol Specification), 3G TS25.322 (RLC Protocol Specification) and 3G TS25.331 (RRC Protocol Specification) in detail.
IMT-2000 systems are the third generation systems which aim to unify the various mobile communication networks and services into one to provide many mobile communication services. The systems can provide multimedia services under multi-environments through various qualities of services and high capacity. Also, in the aspect of services, the systems can provide multimedia services of speech, image and data up to the rate of 2 Mbps and an international roaming. And, in the aspect of network, the systems are total systems which are based on ATM networks and combine fixed and wireless systems.
IMT-2000 system requires new system concept, high-level adaptation technology, and novel network technology, as well all conventional technologies which were already adopted in the second digital cellular system.
As described above, in the next-generation mobile telecommunication system such as the IMT-2000 system, either the GSM-MAP network used in the above conventional asynchronous mobile telecommunications system or the ANSI-41 network used in the above conventional synchronous mobile telecommunications system should be employed as a core network in order to perform an international roaming in a synchronous or asynchronous mobile telecommunications system of an IMT-2000 system.
According to network deployment scenarios, the IMT-2000 system can have the following four interface architectures; first: synchronous mobile stationxe2x80x94synchronous radio networkxe2x80x94synchronous ANSI-41 core network, second: synchronous mobile stationxe2x80x94synchronous radio networkxe2x80x94asynchronous GSM-MAP core network, third: asynchronous mobile stationxe2x80x94asynchronous radio core networkxe2x80x94synchronous ANSI-41 network and fourth: asynchronous mobile stationxe2x80x94asynchronous radio networkxe2x80x94asynchronous GSM-MAP core network.
The IMT-2000 system has the four interface architectures as mentioned above. Therefore, the hybrid type synchronous mobile station must recognize an operating type of a core network currently connected thereto, and the hybrid type synchronous radio network should provide core network operating type information and others information to the hybrid type synchronous mobile station. The core network operating type information and the others information must be contained in the Sync channel message that the synchronous mobile station, after being powered on, receives through the Sync channel in the above-mentioned conventional interfacing manner.
Similarly, the hybrid type asynchronous mobile station must recognize an operating type of a core network currently connected thereto, and the hybrid type asynchronous radio network should provide the core network operating type information and others information to the hybrid type asynchronous mobile station. The core network operating type information and the others information must be contained in the system information message transmitted to the asynchronous mobile station, after being powered on, so that the asynchronous mobile station receives through the broadcast control channel (BCCH) in the above-mentioned conventional interfacing manner.
FIG. 3A is a view showing a synchronous ANSI-41 core network interface architecture of a hybrid type synchronous radio network. In this drawing, the reference numeral 100 denotes a hybrid type synchronous mobile station, 110 a hybrid type synchronous radio network, and 120 a synchronous ANSI-41 core network which includes a synchronous Mobile Switching Center (MSC).
FIG. 3B is a view showing an asynchronous GSM-MAP core network interface architecture of the hybrid type synchronous radio network. In this drawing, the reference numeral 100 denotes a hybrid type synchronous mobile station, 110 a hybrid type synchronous radio network, and 130 an asynchronous GSM-MAP core network which includes an asynchronous Mobile Switching Center (MSC).
FIG. 3C is a view showing an asynchronous GSM-MAP core network interface architecture of a hybrid type asynchronous radio network. In this drawing, the reference numeral 210 denotes a hybrid type asynchronous mobile station, 220 denotes a hybrid type UTRAN which is a hybrid type asynchronous radio network, and 230 denotes an asynchronous GSM-MAP core network which is connected to the hybrid type UTRAN 220 and includes an asynchronous Mobile Switching Center (MSC).
FIG. 3D is a view showing a synchronous ANSI-41 core network interface architecture of the hybrid type asynchronous radio network. In this drawing, the reference numeral 210 denotes a hybrid type asynchronous mobile station, 220 denotes a hybrid type UTRAN which is a hybrid type asynchronous radio network, and 240 denotes a synchronous ANSI-41 core network which is connected to the hybrid type UTRAN 220 and includes a synchronous Mobile Switching Center (MSC).
In order to be operable adaptively to the above four interface architectures, each of the hybrid type synchronous and asynchronous mobile stations in the next-generation mobile telecommunications system has both asynchronous CC and MM protocol entities serving for the GSM-MAP core network and synchronous CC and MM protocol entities serving for the ANSI-41 core network at the layer3 in the protocol stack structure, which is a different from each of the conventional synchronous and asynchronous mobile stations.
FIG. 4A is a view showing the layered protocol structure of a hybrid type synchronous mobile station, a hybrid type synchronous radio network and the synchronous ANSI-41 core network. In this drawing, the reference numeral 100 denotes a hybrid type synchronous mobile station, 110 denotes a hybrid type synchronous radio network, and 120 denotes an ANSI-41 core network which is a synchronous core network connected to the hybrid type synchronous radio network 110.
The hybrid type synchronous mobile station 100 comprises a layer3101, a layer2107 and a layer1108. The layer3101 comprises a synchronous CC part 102, a synchronous MM part 103, an asynchronous CC part 104, an asynchronous MM part 105 and a synchronous radio resource part 106. The hybrid type synchronous mobile station 100 selectively makes a CC/MM protocol active according to a core network operating type. Information for identifying the core network operating type is given to the hybrid type synchronous mobile station 100.
For example, if the hybrid type synchronous mobile station 100 is currently connected to the ANSI-41 core network 120, the layer3101 therein activates protocols of the synchronous CC part 102 and synchronous MM part 103 to perform a message interfacing operation with the ANSI-41 core network 120.
The hybrid type synchronous radio network 110 comprises a layer3111, a layer2115 and a layer1116, which activate their protocols corresponding respectively to those in the hybrid type synchronous mobile station 100 and those in the ANSI-41 core network 120 to transmit and receive messages.
The ANSI-41 core network 120 comprises a layer3121, a layer2125 and a layer1126. The layer3121 comprises a synchronous CC part 122, a synchronous MM part 123 and a synchronous RR part 124.
Functions of each layer in the hybrid type synchronous radio network and the synchronous core network are similar to those in the hybrid type synchronous mobile station, and therefore, detailed description on the functions will be skipped in this specification.
On the other hand, a hybrid type synchronous mobile station, a hybrid type synchronous radio network and an asynchronous core network have layered protocol structures as shown in FIG. 4B when the core network connected thereto is of an asynchronous operating type as shown in FIG. 3B.
In FIG. 4B, the reference numeral 100 denotes a hybrid type synchronous mobile station, 110 denotes a hybrid type synchronous radio network, and 130 denotes a GSM-MAP core network which is an asynchronous core network.
The hybrid type synchronous mobile station 100 comprises a layer3101, a layer2107 and a layer1108. The layer3101 includes a synchronous CC part 102, a synchronous MM part 103, an asynchronous CC part 104, an asynchronous MM part 105 and a synchronous RR part 106. The hybrid type synchronous mobile station 100 selectively makes a CC/MM protocol active according to a core network operating type.
For example, if the hybrid type synchronous mobile station 100 is currently connected to the GSM-MAP core network 130, the layer3101 therein activates protocols of the asynchronous CC part 104 and asynchronous MM part 105 to perform a message interfacing operation with the GSM-MAP core network 130.
The hybrid type synchronous radio network 110 comprises a layer3111, a layer2115 and a layer1116, which activate their protocols corresponding respectively to those in the hybrid type synchronous mobile station 100 and those in the GSM-MAP core network 130 to transmit and receive messages.
The GSM-MAP core network 130 comprises a layer3131, a layer2135 and a layer1136. The layer 3131 includes an asynchronous CC part 132 and an asynchronous MM part 133, an asynchronous RRC part 134.
The layers 3 to 1 of the hybrid type synchronous radio network 110 are connected and correspond respectively to those in the hybrid type synchronous mobile station 100 and those in the asynchronous core network 130. However, the layer3101 of the hybrid type asynchronous mobile station 100 and the layer 3131 of the asynchronous core network 130 are coupled to each other not through the hybrid type synchronous radio network 110.
FIG. 4C is a view showing layered protocol structures of a hybrid type asynchronous mobile station, a hybrid type asynchronous radio network and a synchronous ANSI-41 core network. In this drawing, the reference numeral 210 denotes a hybrid type asynchronous mobile station, 220 denotes a hybrid type UTRAN which is a hybrid type asynchronous radio network, and 230 denotes an ANSI-41 core network connected to the hybrid type UTRAN 220.
The hybrid type asynchronous mobile station 210 comprises a layer3211, a layer2217 and a layer1218. The layer1 includes a synchronous CC part 212, a synchronous MM part 213, an asynchronous CC part 214, an asynchronous MM part 215 and asynchronous RRC part 216 and selectively activates a synchronous CC/MM protocol or an asynchronous CC/MM protocol.
For example, if the hybrid type asynchronous mobile station 210 is currently connected to the ANSI-41 core network 230, the layer 3211 therein activates a protocol between the synchronous CC part 212 and synchronous MM part 213 to perform a message interfacing operation with the ANSI-41 core network 230.
FIG. 4D is a view showing layered protocol structures of a hybrid type asynchronous mobile station, a hybrid type asynchronous radio network and an asynchronous GSM-MAP core network. In this drawing, the reference numeral 210 denotes a hybrid type asynchronous mobile station, 220 denotes hybrid type a UTRAN which is a hybrid type asynchronous radio network, and 240 denotes an asynchronous GSM-MAP core network connected to the hybrid type UTRAN 220.
The hybrid type asynchronous mobile station 210 comprises a layer3211 having a NAS part and an AS part, a layer2217 and a layer1218. The NAS part includes a synchronous CC part 212, a synchronous MM part 213, an asynchronous CC part 214 and an asynchronous MM part 215 and selectively activates a synchronous CC/MM protocol or an asynchronous CC/MM protocol. The AS part includes an asynchronous RRC part 216.
The hybrid type asynchronous radio network 220 comprises a layer3221, a layer2225 and a layer1226, which activate their protocols corresponding respectively to those in the hybrid type synchronous mobile station 210 and those in the GSM-MAP core network 240 to transmit and receive messages.
The GSM-MAP core network 240 comprises a layer3241 having a NAS part and an AS part, a layer2245 and a layer1246. The NAS part includes an asynchronous CC part 242 and an asynchronous MM part 243. The AS part includes an asynchronous RRC part 244.
For example, if the hybrid type asynchronous mobile station 210 is currently connected to the GSM-MAP core network 240, the NAS part therein activates protocols of the asynchronous CC part 214 and asynchronous MM part 215 to perform a message interfacing operation with the GSM-MAP core network 240.
The layers 3 to 1 of the hybrid type asynchronous radio network 220 are connected and correspond respectively to those in the hybrid type synchronous mobile station 210 and those in the asynchronous core network 240. However, the NAS parts of the hybrid type asynchronous mobile station 210 and the asynchronous core network 240 are coupled to each other not through the hybrid type asynchronous radio network 220.
A communication protocol between a synchronous mobile station and a synchronous mobile network is referred to an Air-interface protocol. For example, a TIA/EIA/IS2000 protocol is used as the Air-interface protocol.
A communication protocol between a synchronous radio network and a synchronous core network, for example, an ANSI-41 network is referred to an A-interface protocol. For example, a three generation interoperablility specification (3G-IOS) is used as the A-interface protocol.
In case of an asynchronous communication system, in other words, in a system having an asynchronous mobile station, an asynchronous mobile network and an asynchronous core network, each of the asynchronous mobile station and the asynchronous mobile network has a RRC protocol entity and communicates messages used in the RRC protocol entity with each other.
The RRC protocol entity means a protocol entity which manages and controls a radio resource between the asynchronous mobile station and the asynchronous mobile network. The radio resource management and control are performed by a message defined in the RRC protocol entity (as is referred to xe2x80x9ca RRC messagexe2x80x9d in this specification).
The RRC messages can be classified according to its function as follows:
1) RRC message related to a connection management;
2) RRC message related to a radio bearer;
3) RRC message related to a connection mobility; and
4) RRC message related to a measurement control.
The RRC message related to a connection management includes information related to a connection and release between the asynchronous mobile station and the asynchronous mobile network, operations after connection and information to be broadcasted to the mobile station.
The RRC message related to the radio bearer includes RRC messages having information related to an allocation of the radio resource between the asynchronous mobile station and the asynchronous mobile network, a reconfiguration of the radio resource, etc.
The RRC message related to the connection mobility includes RRC messages having information related to a mobility of the mobile station and a handover.
The RRC message related to the measurement control includes RRC messages having information related to measurement, confirmation and management of a present configuration of the radio resource.
The RRC messages includes information elements as follows:
1) Information element related to a core network;
2) Information element related to a mobility of UTRAN;
3) Information element related to a UE;
4) Information element related to a radio bearer;
5) Information element related to a transport channel;
6) Information element related to a physical channel; and
7) Information element related to a measurement.
All or a part of information elements are included in each of the RRC messages. Each of the information elements has a plurality of information fields. All or a part of the plurality of information fields are communicated between the mobile station and the radio network in accordance with a function and a use.
Each of the asynchronous mobile station and the asynchronous radio network stores and uses the information elements related to the radio resource, the information elements included in the RRC message, in the RRC protocol entity. Each of the asynchronous mobile station and the asynchronous radio network stores and uses the information elements not related to the radio resource in the CC/MM protocol entity included in the layer3.
The RRC messages, the information elements included in the RRC message and the information fields included in the information elements are defined for the asynchronous communication system.
However, in the IMT-2000 system, the asynchronous mobile station and radio network can be coupled to the synchronous core network. Accordingly, if the present information elements having the present information fields are used, the asynchronous mobile station cannot be interfaced with the synchronous core network.
In order to interface the asynchronous mobile station and the radio network with the synchronous core network, the information elements should have information fields used for the synchronous CC/MM protocol entity.
Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to provide a method for transmitting a radio resource control (RRC) message in an asynchronous mobile communication system regardless of an operating type of a core network coupled to the asynchronous mobile communication system network.
In accordance with one aspect of the present invention, there is provided a method for transmitting a radio resource contorl (RRC) message from an asynchronous mobile station to an asynchronous radio network in an asynchronous mobile communication system, the method comprising the steps of: a) determining whether a core network is a synchronous core network or an asynchronous core network; b) if the core network is the synchronous core network, generating a RRC message having information related to the synchronous core network; and c) transmitting the RRC message to the asynchronous radio network.
In accordance with another aspect of the present invention, there is provided a method for transmitting a radio resource control (RRC) message from an asynchronous radio network to an asynchronous mobile station in an asynchronous mobile communication system, the method comprising the steps of: a) determining whether a core network is a synchronous core network or an asynchronous core network; b) if the core network is the synchronous core network, generating a RRC message having information related to the synchronous core network; and c) transmitting the RRC message to the asynchronous mobile station.